Lattice oxygen assisted room-temperature catalytic process: Secondary alcohol dehydrogenation over Au/birnessite photocatalyst

Abstract

Au-based catalysts were widely applied in photocatalytic areas owing to Au local surface plasmon resonance (LSPR), especially in the reactions of secondary alcohol dehydrogenation. However, there were rare cases reporting Au catalysts to dehydrogenate secondary alcohols under dark condition at room temperature. In this work, basic semiconductor birnessite, with easily extractable lattice oxygen in its lattice structure, was employed as support of Au catalyst and it was found that the Au/birnessite catalyst could dehydrogenate iso-propanol (IPA) to acetone under dark condition (3.7μmol acetone was produced within 5h). With the utilization of lattice oxygen in the reaction under dark condition, oxygen vacancies were instantaneously formed which enhanced the light absorbing properties of Au/birnessite and further improved its photocatalytic activity (13.6μmol acetone production within 5h). The synergistic effects between lattice oxygen and oxygen vacancies enhanced the performance of Au-based catalyst in IPA dehydrogenation and this work provides a synthesis tactic for effective catalysts in the dehydrogenation of various secondary alcohols.